Ergodic Capacity and Information Outage Probability of MIMO Nakagami-m Keyhole Channels with General Branch Parameters

The authors derive exact analytical closed-form expressions for the ergodic capacity and information outage probability of multiple-input multiple-output (MIMO) keyhole channels in Nakagami-m fading environments. In this regard, the authors consider the most general case with channel coefficients having not necessarily identical fading parameters and average power gains, respectively. The ergodic capacity is given as a finite sum of weighted Meijer G-functions, which might be easily evaluated numerically. Additionally, the authors provide somewhat simpler upper and lower bounds, which can be expressed by means of elementary functions only and which are proven to be asymptotically tight for high signal-to-noise ratios. Numerical results are shown to be in perfect agreement with results obtained from Monte-Carlo simulations, thus verifying the accuracy of our theoretical analysis.